LIGHT DIMMER
Triac dimmer used to control lamp up to 1000W
Many times it is required to control the power of incandescent lamps. This simple circuit of Light Dimmer can control power up to 1000W. The circuit operates on the phase-control principle. The power operated devices like diac and triac are used for controlling the output power.
LISTENING BUG
Used to listening voice the people sitting in the nearby room.
How great, if you are able to listen the people sitting in the adjoining room. This project provides an effective way to this imagination.
This is a very simple and inexpensive circuit uses an operational amplifier IC 741 (IC1) and push-pull amplifier using transistors for amplification of a signal.
MELODY GENERATOR
The BT8031 series are CMOS LSI chip is designed for use in doorbell, telephone and toy applications. They are on chip ROM programmed for musical performance produced by CMOS technology, these devices result in very low power consumption, since the BT8031 include oscillating and mode selection circuit, a compact melody module can be constructed with only a few additional components.
NOVEL LIGHT EFFECT
A bunch of LEDs flashes, which gives novel light effect.
This simple, low cost novel light effect circuit can be used for many purposes like decoration, display board etc. It uses total 88 LEDs and a bunch of 11 LEDs will glow at a time. After a few seconds another bunch glows and the cycle repeats.
POLICE / AMBULANCE SIREN
Introduction:
There are different types of siren tones used for different purposes like ambulance, police fire etc. The siren kits available in the market generate normally a single tone. With multitone siren kit, we can generate different types of siren tones for different purposes. This unique feature of the circuit makes it versatile and useful in wide range of applications like burgler system, lift door open alarm, smoke detector and any other alerting application.
SOUND OPERATED TIMER
THREE TUNE MUSICAL BELL
The UM 66T series are CMOS LS is designed for use in doorbell, telephone and toy applications. They are on chip ROM programmed for musical performance produced by CMOS technology, these devices result in very low power consumption, since the UM 66T series include oscillating and mode selection circuit, a compact melody module can be constructed with only a few additional components.
TIMER WITH BUZZER INDICATOR
ON/OFF Timer with audible warning from 1 to 100 min delay
This circuit is used as portable parking meter timer and egg timer. The 14 stage binary ripple counter type IC 4060 has an onchip oscillator capable of stable operation over a relatively wide frequency is determined by an external RC network connected to pins 9,10 and11.